Analysis of Vestibular Evoked Myogenic potentials in Migraines individuals attending a Tertiary Care Hospital
S. Mahalakshmi1, Dr.K.Subramaniyan*1, A.S.Naziyagulnaaz2
1.Department of Neuroscience Technology, Faculty of Allied Health Sciences, Chettinad Academy of Research and Education (CARE), Kelambakkam, Tamil Nadu.
1.Professor and HOD-Department of Neurology, Chettinad Hospital and Research Institute (CHRI), Chettinad Academy of Research and Education (CARE), kelambakkam, Tamil Nadu.
2.Research Assistant, Faculty of Allied Health Science, ChettinadAcademy of Research and Education (CARE), Kelambakkam, Tamil Nadu.
Corresponding author*
Dr.K.Subramaniyan,
Professor and HOD-Department of Neurology, Chettinad Hospital and Research Institute (CHRI), Chettinad Academy of Research and Education (CARE),
kelambakkam, Tamil Nadu, India.
Abstract:
Introduction:Migraine is a neurologic disease, often associated with a unilateral throbbing pain, which is categorized under primary headache disorder according to the International headache society (ICHS-3) beta edition. Migraine is the 3rd most prevalent illness and also the 6th most disabling illness in the world. Female:
Male ratio: (3:1). Vestibular dysfunctions are frequently associated with migraine including the common type.
Material and method:
The cross observational study was done among the patients who had migraine in Chettinad super speciality hospital, kelambakkam over my study period. Participants who fulfill the international classification of Headache Disorders criteria were recruited from the Neurology OPD. Subjects are enquired about their history of diagnosis, Family history, Investigations and diagnostic tests such as cVEMP
Results:Prolonged latencies are likely due to the degradation of central vestibular processing of otolith signals rather than a decline in peripheral vestibular function . VEMP amplitudes can be used as independent quantitative measures of otolith function. Several studies have reported that Abnormal VEMP potentials and Amplitude asymmetry are seen in Migranious individuals. Even though migraine is not an inner ear disorder, but of the brain, generally lower threshold is noted in migraine individuals. Conclusion:Migraine have very few available diagnostic tests with less statistical significance, VEMP studies on migraine patients may shed new light on its pathophysiology as well as only p13 and amplitude were considered .N23 0r N1 potential was used for only identifying p13.
Introduction:
Migraine is a neurological condition, characterized by episodic varying intensity (Mild Moderate - severe) headaches, which usually lasts for hours to days, begins unilaterally, but may spread bilaterally. Migraine may be accompanied by any combination of symptoms such as visual disturbances, hypersensitivity to light, sound and smell, inclination to vomit, vomiting and vestibular manifestations [1]. These manifestations will differ from individual to individual and persons may have different symptoms during different episodes. Each episode may vary in duration and occurrence.The ICHD – 3 (International classification of Headache disorders) classify several types of headaches that includes different manifestations [2]. Migraine is categorized under primary headache disorder according to ICHD -3 with many subdivisions depending upon specific features, but commonly migraine descends under two major groups : Migraine with Aura, Migraine without Aura [14].The aura indicates “Warning sign”, is the multiplex of neurological symptoms such as sensory, Speech, visual, Motor and other central nervous symptoms, which can exist for minutes in length and is reversible [3]. The aura’s can be unilateral, that usually happens before the headache, but it may also happens after or persists with the phase of headache has commenced. The term called “Silent migraine”
defines aura which may experienced by individuals without headache episodes.
The episodes of migraine attacks without warning signs, which generally lasts for 4 – 72 hours when it’s treated or unsuccessfully treated. Manifestations include unilateral throbbing or pulsating pain accompanied with Vomiting or inclination to vomit, hypersensitivity to smells, Sounds and light, mood changes, fatigue, confusion and visual disturbances [4]. Migraine headache may be exacerbated by performing physical tasks (Walking or climbing stairs) and during menstrual cycles. Moreover, the migraine without aura is more vulnerable to worsen with recurrent use of symptomatic medications [5].The symptoms of migraine may differ according to many phases, depending on what the individual was in. A migraine may happen in 4 stages, but it’s not mandatory that all migraine individuals should experience all the stages [6]. (1)The Prodromal Stage, (2) The Aura stage, (3) The Attack stage, (4) The Postdromal Stage.The prodromal stage also known as prodrome or preheadache stage / phase. It may happen hours or even days before the migraine episode. The prodromal stage can be viewed as warning sign migraineur’s “Yellow light” which alerts individuals as well as doctors of an forthcoming migraine [7]. The manifestations of this stage are often attributed to medications taken to recover from migraine [13].
In this study to analyse the vestibular evoked myogenic potentials in migraine individuals attending a tertiary care hospital and to identify the potential changes and abnormalities if any which could be specific to migraine [16]. The cross observational study was done among the patients who had migraine Participants who fulfil the international classification of Headache Disorders criteria were recruited from the Neurology OPD.
Subjects are enquired about their history of diagnosis, Family history, Investigations and diagnostic tests such as cVEMP.[15] VEMP study of 58 Migrainous individuals’ shows abnormal findings in 65% of patients and normal findings in 34% of patients. Though, 65% of patients had abnormal VEMP findings, there is no statistically significant correlation with location of headache or pain intensity [17]. Further studies with larger sample sizes, preferably with case and controls are required to corroborate the findings of this study.
Materials and method:
Observational cross sectional study. 58 patients presenting with complaints of migraine in attending chettinad hospital and research institute during this study period to analyse the vestibular evoked myogenic potential changes in migraine individuals attending a tertiary care hospital. Minimal sample size requirement for the study is calculated using the formula (p =0.04); (q=1-p); (d=0.05); n=p*q (1.96/d)2 and the minimum sample size requirement was 58. Inclusion Criteria: (a) Age > 18 years, (b) Patients who fulfil ICHD-3β edition (1.1 and 1.2) diagnostic criteria for migraine according to International Headache Society. Exclusion Criteria:(a) Technical difficulty: Patients with pericranial, neck and shoulder muscle tenderness and/or associated myofascial pain syndrome. Because these conditions can affect muscle tension or posture during method leads to the degree of muscle contraction affects the cVEMP result and its interpretation,(b)Patient having a chronic neurological, systemic or inner ear / auditory condition indicating an otological disorder that would affect the results of VEMP analysis or a past cervical trauma.
Statistical Methods:
The statistical analysis was performed using the SPSS software package (version 21.0, SPSS, Chicago, IL, U.S.A.). Descriptive statistics will be applied to calculate demographic variables like Mean, Median, Standard, Deviation, Confidence interval P values are calculate. Pie chart /Bar graph will be used to explain the cVEMP changes in migrainous individual. The student t-test was executed to determine the significant change in mild (right) between moderate (left) and severe (bilateral) latencies were compared. Further, the Pearson’s correlation analysis was carried to determine the interdependency between the pain severities. The statistical significant was considered, if p-value < 0.05.
RESULTS BASED ON AGE:
AGE (IN GROUPS)
MIGRAINE WITH AURA
PERCENTAGE MIGRAINE WITHOUT AURA
PERCENTAGE
20 years or less 1 3 2 8
21-30 years 15 48 12 45
31-40 years 7 23 6 22
41-50 years 1 3 3 11
51-60 years 4 13 2 7
61-70 years 2 7 2 7
> 70 years 1 3 0 0
TABLE: 1.0
Figure 1
The above table 1.0 shows number of patients in the study who had migraine with aura or without aura and their age wise distribution. The chart 1 shows graphical representation of age wise distribution. Among 58 patients, incidence of migraine is maximum in age group of 21 - 30 years MWA 48 %, MWOA 45 %.
BASED ON GENDER:
GENDER NUMBER PERCENTAGE
MALE 14 25
FEMALE 44 75
TABLE: 1.1
Figure 1.1
MWA MWOA VEMP FINDING
GENDER NUMBE
R
% NUMBER % NOR
MAL
ABNORM AL
% %
Male 7 50 7 50 3 11 21 78
Female 23 48 21 48 17 27 38 61
X2 testsTABLE: 1.3
Value Df P
X2 1.39 1 0.238
N 58
Figure 1.2
The above table 1.3 and chart 1.2 shows gender distribution of patients in this study. The table 5.3 shows Out of 58 participants, 50 % of male and 48 % of female had migraine with aura and 50% male and 48 % of female had migraine without aura. Normal male 21%, Female 38%, Abnormal male 78%, Female (61%).Based on gender, p value 0.238, is not statistically significant. The above chart 3 shows graphical representation of migraine patients with aura and without aura based on gender. On based on gender analysis, the increased incidence of migraine is noted in female population.
BASED ON PAIN SEVERITY:
Figure 1.3 CHART: 4 TABLE: 1.3
PAIN
INTENSITY
% PERECENT
AGE
MIGRAINE WITHOUT
%
AURA
MILD 4 12 4 17
MODERATE 6 18 8 35
SEVERE 24 70 11 48
The above table 1.3 shows incidence of migraine with aura and without aura based on pain severity. The above chart 4 shows graphical representation of migraine with aura and without aura based on pain severity.
Based on pain severity, increased incidence of severe pain intensity 70 % in migraine with aura and 48 % in migraine without aura is noted. The above table 5.4 shows incidence of migraine with aura and without aura based on pain severity. The above chart shows graphical representation of migraine with aura and without aura based on pain severity Based on pain severity, increased incidence of severe pain intensity 70 % in migraine with aura and 48 % in migraine without aura is noted.
BASED ON LOCATION:
LOCATION OF HEADACHE
MIGRAINE WITH AURA
% MIGRAINE WITHOUT AURA
%
RIGHT 8 29 14 46
LEFT 7 25 5 17
BILATERAL 13 46 11 37
TABLE: 1.4
Figure 1.4
The Above table 1.4 shows incidence of migraine with aura and without aura based on location of headache.
The Above chart 5 shows graphical representation of migraine with aura and without aura based on location of headache. Based on location of headache, the increased incidence of bilateral headache 46 % in migraine with aura and increased incidence of right sided headache 46 % in migraine without aura.
VEMP LATENCIES CORRELATION: (p13 latency) BASED ON LOCATION:
Figure 1.5
LOCATIO N
OF
HEADACH E
PROLON GED LATENC Y ON RIGHT
% PROLONG ED
LATENCY ON LEFT
% PRONLONGE D LATENCY ON BOTH SIDES
% NORMA L LATEN CY
%
RIGHT 11 50 0 0 2 9 9 41
LEFT 0 0 6 50 0 0 6 50
BILATERA L
2 8 3 12 3 13 16 67
TABLE: 1.5
The above table 1.5 shows correlation of VEMP latencies based on location of location of headache. The above chart 7 shows Right - 50 % of unilaterally prolonged latencies, nil % of latency prolongation on contralateral side, 9% of bilaterally prolonged latencies and 41 % of normal latencies. Left - 50 % of unilaterally prolonged latencies, nil % of latency prolongation on contralateral side, Nil % of bilaterally prolonged latencies and 50 % of normal latencies. Bilatera l – 8 % of latencies prolonged on right side, 12 % of latencies prolonged on left side, (13 %) of latency prolonged on both sides and 67 % of normal latencies.
On whole, Out of 58 participants, In unilateral headache, maximum number of VEMP latency prolongation is noted on same side, Right sided headache 50 %, left sided headache 50 %, In patients with bilateral sided showed normal latency.
VEMP LATENCY CORRELATION BASED ON PAIN SEVERITY: ( p 13 latency) BASED ON PAIN SEVERITY:
Figure 1.6
PAIN SEVERITY
PROLONGED LATENCY ON LEFT SIDE
% PROLONGED LATENCY ON
RIGHTSIDE
% PRONLONGE D LATENCY ON BOTH SIDES
% NORMAL LATENCY
%
MILD 2 25 0 0 0 0 6 75
MODERAT E
5 33 1 7 2 13 7 47
SEVERE 3 9 11 31 3 9 18 51
TABLE: 1.6
The Above table 1.6 shows prolonged latencies based on pain severity: The above chart 8 shows Mild - 25 % of prolonged latencies on left side, 75 % of Normal latencies is noted, hence in mild pain intensity – no significant latency prolongation, Moderate – 33 % of prolonged latencies on left side, 7 % of prolonged latencies on right side, 13 % of prolonged latencies on bilateral side and 47 % of normal latencies is noted, hence in moderate pain intensity – no significant latency prolongation. Severe – 9 % of prolonged latencies on left side, 31 % of prolonged latencies on right side, 9% of prolonged latencies on bilateral side and 51 % of normal latencies is noted, hence in severe pain intensity – no significant latency prolongation. On whole, Out of 58 participants, no significant latency prolongation based on pain severity.
Independent Samples T-Test TABLE: 1.7 Independent Samples T-Test
LATENCIES T-TEST STATISTICS df p RIGHT P13 Student's t -2.463 ᵃ 56.0 0.17 LEFT P13(ms) Student's t -2.500 ᵃ 56.0 0.015
LEFT N23 (ms) Student's t 1.099 ᵃ 56.0 0.277 RIGHT N23
(ms)
Student's t -0.355 56.0 0.724
Levene’s test is significantly (p<.05), suggesting a violation of the assumption of equal variances. In this table 1.7 p13 latency shows statistical significance. N23 has no statistical significance
VEMP AMPLITUDES CORRELATION: BASED ON LOCATION OF HEADACHE:
LOCATIO N OF HEADACH E
AMPLITU DE
ASYMME TRY ON UNILATE RAL SIDE
% AMPLITUD E
ASYMMET RY ON CONTRAL ATERAL SIDE
% AMPLITUD E
ASYMMET RY ON BOTH SIDES
% NORMA
L
AMPLIT UDE
%
RIGHT 11 50 0 0 3 14 8 36
LEFT 9 75 0 0 0 0 3 25
BILATERA L
2 8 0 0 4 17 18 75
TABLE: 1.8
Figure 1.7
The above table 1.8 shows amplitude asymmetry based on location of headache. The above chart shows Right - 50 % of amplitude reduction in right, Nil % of amplitude reduction in left, 14 % of amplitude reduction in bilateral sides, 36 % of normal amplitudes is noted. Left – Nil % of amplitude reduction in right, 75 % of amplitude reduction in left, nil % of amplitude reduction in bilateral sides, 25 % of Normal amplitudes is noted. Bilateral – 8% of amplitude reduction in right, nil % of amplitude reduction in left, 17 % of amplitude reduction in bilateral sides, 75 % of normal amplitudes is noted. In unilateral headaches, right side shows 50
%of amplitude reduction and left side75 % reduction on same side. In bilateral headaches 75 % of normal amplitudes are noted.
BASED ON VEMP FINDINGS:
VEMP FINDINGS
RIGHT LEFT BILATERAL TOTAL
NORMAL 6 3 3 20
ABNORMAL 16 9 13 38
TOTAL 22 12 24 58
X2 tests Value Df p-value
X2 2.35 3 0.308
N 58
TABLE: 1.9
Figure 1.8
The VEMP findings showed right sided headache Normal VEMP in 30 %, Abnormal VEMP in 42 %, Left sided headache Normal VEMP in 15 %, Abnormal VEMP in 23 %, Bilateral headache Normal VEMP in 15
%, Abnormal VEMP in 34 %. P value 0.308 which shows less statistical significance. The above chart shows graphical representation of normal and abnormal VEMP findings on whole, the increased incidence of abnormality on right sided headache is noted.
Discussion:
Among 58 patients, Based on age, incidence of migraine is maximum in age group of 21 - 30 Years MWA 48
%, MWOA 45 % [27]. Based on gender analysis, the increased incidence of migraine is noted in female population 50 % of male and 48 % of female had migraine with aura and 50% male and 48 % of female had migraine without aura, Normal male 21%, Female 38%, Abnormal male 78%, Female 61% based on gender and also shows p value 0.238, which is not statistically significant [26]. Based on pain severity, increased incidence of severe pain intensity 70 % in migraine with aura and 48 % in migraine without aura is noted.
Based on location of headache, the increased incidence of bilateral headache 46 % in migraine with aura and increased incidence of right sided headache in migraine without aura. Based on associated symptoms, photophobia 24 % and vertigo / giddiness 18 % are the most common associated symptoms [25]. Based on VEMP latencies correlation headache location, in unilateral headache, maximum number of VEMP latency
prolongation is noted on same side, Right sided headache 50 %, left sided headache 50 %, in patients with bilateral sided showed normal latency. Based on VEMP latencies correlation with pain severity - No significant latency prolongation. Based on VEMP amplitude correlation with location of headache - On whole, In unilateral headaches, right side shows 50 %of amplitude reduction and left side75 % reduction on same side [22-24]. In bilateral headaches 75 % of normal amplitudes is noted. Based on VEMP findings, right sided headache Normal VEMP in 30 %, Abnormal VEMP in 42 %, Left sided headache Normal VEMP in 15
%, Abnormal VEMP in 23 %, Bilateral headache Normal VEMP in 15 %, Abnormal VEMP in 34 %. P value 0.308 which shows less statistical significance. On whole, the increased incidence of abnormality on right sided headache is noted [18-21]. In this table p13 latency shows statistical significance. N23 has no statistical significance. Several studied revealed that migraine patients with no or delayed VEMPs [39,38]. The findings of the present study tend to lean towards central vestibular disorders in this disease [35-37]. In my study, 22 migraine patients with Right side pain, 12 patients with left side pain and 24 patients with bilateral pain participated [40]. Based on VEMP latencies correlation headache location, right sided headache shows high significant percentage of latency prolongation on unilateral side compared to both left and bilateral. Based on VEMP latencies correlation with pain severity - No significant latency prolongation is noted. Based on VEMP amplitude correlation with location of headache [30-34]]. Unilateral headaches showed significant amplitude reduction on ipsilateral side compared to bilateral headaches may be due to lower threshold levels at the headache site. Based on VEMP Findings right sided headache showed more VEMP abnormality 42 %.
CONCLUSION:
VEMP study of 58 Migraine’s individuals’ shows abnormal findings in 65% of patients and normal findings in 34% of patients [28]. Though, 65% of patients had abnormal VEMP findings, there is no statistically significant correlation with location of headache or pain intensity [29]. Further studies with larger sample sizes, preferably with case and controls are required to corroborate the findings of this study.
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